Dowel



M. T. RUDDY April 29, 1941.

BY finer/H. .Euom

ATTORNEYS Patented Apr. 29, 1941 UNITED STATES PATENT OFFICE DOWEL Martin T. Ruddy, Lakewood, Ohio Application October 27, 1939, Serial'No. 301,646

4 Claims. (01. 22-158) This invention relates to dowels that are used in connection with patterns for. making castings. While the invention is particularly applicable to dowels, it is also applicable to other plates for use in connection with'patterns, and also for secured that it will withstand the severe service,

to which such devices are subjected without becoming loose or interfering with the closing of the parts of the pattern.

Other objects of the invention and the features of novelty will be apparent from the following description when taken in conjunction with the accompanying drawing, of which Fig. 1 is a cross section through a dowel embodying my invention, the section being on the line |l of Fig. 4.

Fig. 2 is a similar view of the companion plate for the dowel, the section being on the line 2--2 of Fig. 5.

Fig. 3 is a transverse section illustrating the parts, shown in Figs. 1 and 2, in assembled relation.

Fig. 4 is a plan view of the dowel.

Fig. 5 is a plan view of the companion plate.

Fig. 6 is a side elevation of the dowel shown in Fig. 4.

Fig. 7 is a plan View of a surface of a pattern and illustrating the manner of attaching the dowel and its companion plate to the pattern.

Referring to Figs. 1 and 4, it will be noted that the dowel proper, which is indicated by the numeral I9, is formed integral with a plate H of substantially triangular form and provided with a marginal flange l2. At the corners of the triangular plate ll there are circular lugs l3, l4 and IS, the centers of which are located at the points [6, I1 and I8, respectively. The centers l6, l1 and iii are preferably located on a circle I 9 having its center at the point which is the axis of the dowel l0. Each of the lugs l3, l4 and i5 is provided with a screw opening 2|, the centers of these openings being preferably at the centers I6, I! and I8, respectively.

On the bottom surface of the plate ll there are pointed projections or lugs 22 which are symmetrically positioned to one side of the openings 2|v and on the circle [9 as will be noted from Fig. 4.

Referring to Fig. 7, the points 23, 24 and 25 represent impressions made in the surface of the pattern, at the point wherethe dowel is to be located, these impressions being formed by locating the dowel on the pattern, as shown in Fig. 6,

and then striking the dowel ID with a hammer. The impressions 23, 24 and 25 are then used as centers for boring holes in the pattern, these holes being of the same diameter as the lugs l3, l4 and I5. After the three holes have been bored to the proper depth, the dowel is laid on the pattern with the lugs I3, l4 and IS in registration with the bored holes, and lines are then drawn on the pattern along the sides 26, 21 and 2B. The dowel is then removed and the recess for the plate His completed, the plate positioned in the recess and fastened by means of screws 29 placed in the openings 2|. On the upper side of the plate I l, adjacent each of the screw openings 2|, there is an upstanding lug or projection 30 and, when the screws 29 are in position, these lugs are bent over the heads of the screws as indicated in Fig. 3, so that the screws 29 are prevented from coming out. Heretofore trouble has been experienced with screws for fastening dowel plates because the jolting that the patterns get in service, particularly in molding machines, has a tendency to cause the screws to work out until they interfere with the closing of the parts of the pattern.

On account of the plate ll being of triangular or polygonal form, and because of the accuracy with which the recess may be made in the pattern to receive the plate, as above described, the plate will be very firmly secured to the pattern and prevented from moving laterally. Inthis connection, and as an efiicient means for securing accuracy in the size and shape of the recess to receive the dowel plate, the lugs l3, l4 and [5 are preferably made with a diameter the same as that of a standard auger, such as threefourths inch, one inch, or larger, and since the centers of the lugs are accurately located by means of the projections 22, it is possible to so form the recess in the pattern that the dowel plate will accurately and tightly fit it and thus have lateral support in addition to the support given by the attachment screws 29.

The companion plate shown in Figs. 3 and 5 is similar to the plate of the dowel l0, except that it has the opening 3| to receive the dowel Hi.

In order that the parts of the pattern will be held in proper registration by the dowel, it is important that the two plates be accurately located in the two matching parts of the pattern and, in order to accomplish this, the companion plate, shown in Figs. 3 and 5, is first attached to one part of the pattern in the manner above described with reference to the plate I I. A hole 32 may be bored in the pattern to receive the dowel ID, as shown in Fig. 3. The plate I I is then placed on the companion plate, as shown in Fig. 3, and the part of the pattern to which the plate I I is to be attached is placed in accurate registration with its matching part to which the companion plate is attached. The projections 22 are then caused to indent the pattern, by a blow or otherwise, as previously described, and this will accurately locate the centers I6, I! and I8 so that the procedure, above described, for forming the recess for the plate I I may then be followed.

While I have illustrated and described what I now consider to be the preferred form of my in-,

2. A device of the class described comprising a plate having a marginal flange which forms a recess on one side of the plate, said plate having a plurality of screw openings therein and integral lugs in said recess and adjacent said openings, said lugs being adapted to be bent over the heads of screws in said openings to prevent the screws coming out.

3. A device of the class described comprising a plate of substantially polygonal form having circular lugs at its corners, said plate having a marginal flange projecting above the surface of ,one side of the plate, said lugs having openings vention, it will be understood that changes in the details of construction may be-made without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, I claim:

1. A device of the class described comprising a non-circular plate having a plurality of screw openings therein, said plate having lugs with circular peripheries the centers of which are coaxial with said screw openings, said screw openings having their centers located on a circle, and said plate having pointed lugs projecting from one side thereof and arranged on said circle in the same relative spacing as the centers of said screw openings.

therein for screws, and said plate having integral "lugs projecting from said surface and located adjacentsaid openings, said last-mentioned lugs being adaptedto be bent over said openings.

4." As a new article of manufacture, a plate for patterns V and the like having a substantially polygonal form with circular lugs at its corners provided with screw openings therein, the centers of said lugsbeing located on a circle, said plate having a marginal flange, which projects above the surface of one side of the plate, and integral projections on said surface adjacent said lugs, the other side of said plate having pointed projections located on said circle symmetrically with respect to the centersof said lugs.

MARTIN T. RUDDY. 

